Well N-1 in Mahakam Sisi Nubi field, East Kalimantan, had a problem with water and condensate production up to 11,000 BLPD which instantly rendered the production facility overwhelmed despite the high 34 MMSCD gas rate. To solve this, reservoir production profiling using production logging tool was first carried out. Selection of existing zone isolation method was then compared, yet none satisfies the challenges in this well due to restriction and cost issues. A relatively new technology, High Expansion (HEX) Straddle Packer, was introduced as another alternative. A series of engineering design and followed by operation design was then carried out to solve the well problem safely. A dummy tool run with 2.875" OD and 30ft of length passed through the restriction safely. Caliper logging observes reduction in tubing ID from 3.9" to 3.0". Temperature of the borehole reached 115 deg C at 3417 mBRT of this well. The two water producing zones were next to each other with a total top reservoir to bottom reservoir length of 11 m. With these values, a custom 2.7" straddle packer was built and tested to required temperature and passed. Production simulation with 0.7" ID, indicated the well could still flow over its critical flow regime. After installation, the well flows with 11 MMSCFD of gas with ~1800 BLPD liquid produced, a 83% reduction over previous liquid flowrate. Despite the well flows only 30% from initial gas rate, this well can now flow at an acceptable liquid rate. The successful installation of the first HEX Straddle expands the portfolio of mechanical water shut off methods in Mahakam and in Indonesia as this was the first HEX Straddle installed in Indonesia. Further study and replications are needed, yet this method can be a viable alternative if other has failed for wells with similar problems.

Nowadays oil and gas industry are encouraging the independents and majors to take a fresh look at the technology and concepts required to develop marginal shallow water fields using a minimal platform approach. Innovation on well intervention means (lighter, smaller and less footprint) that fit for Offshore Minimalist Platform (OMP) is needed, including optimizing time and cost during well intervention activities in OMP. To achieve the objectives, well intervention innovation and technology are the main focuses. Intervention activities commonly done on campaign basis with several units (slickline, wireline, coiled tubing, testing) shall be integrated in a safe manner. The approach of integration shall signify these points:Identifying potential jobs in OMP to be done by well intervention methodsIdentifying necessary well intervention means and methods to support the jobs (combo unit, micro coil, hazardous zone redefinition, remote operation)Creating project planning and schedulingPerforming site visit and risk assessmentImplementation and operational executionEvaluation of overall project execution result The following results were obtained after the integration performed:No major safety issues during operationExemplary method and risk assessment for well intervention activities which can be applied for next campaignsTrials on well intervention new units and method (combo unit, micro coil, hazardous zone redefinition, remote operation), were safely performed with some optimization100% success ratio60% on supply boat arrangement35% efficiency in N2 consumption for CT operation45% efficiency in diesel consumption20% - 40% efficiency in Rig Up Time28% less in Job Cost compared to conventional unit These innovations are proven as reliable method to answer OMP challenges with main advantages on footprint and cost optimization. Through this paper, we would like to share lucrative well intervention breakthrough and innovation in OMP with measurable milestones.

The objective of this paper is to present the Mechanical Water Shut-Off (MWSO) strategy for multilayer reservoirs on tubingless well. With 10 open perforated reservoirs and no selectivity option, isolation on water producing reservoir will be the main challenge since production is commingled throughout the lifetime of well. Regular production tests performed through a Multiphase Flowmeter equipment on each offshore platform is a first indicator to monitor the evolution of water production in a well. JM-X well has been experiencing water breakthrough since one week after initial perforation and WGR keep increasing following gas production decline. The strategy was initiated by conducting a bottom hole monitoring survey to identify water sources. Production Logging Tool (PLT) was used to precisely monitor pressure, temperature, water holdup, and fluid rate along the wellbore for further water source and production allocation analysis. Once the water source reservoirs have been identified, MWSO operation was requested. There are several types of MWSO equipment that are commonly used in Offshore Mahakam field each of which has selective economic consideration based on the expected well reserve. Considering operation difficulties and cost, MWSO program was made then will be monitored during the operation time to ensure the operation runs safely and smoothly. MWSO strategy on well JM-X was proven to be able to reduce water production from 900 bpd to only 20 bpd with a significant gain of gas production from 3 MMscfd to 9.2 MMscfd and oil production from 200 bpd to 750 bpd.

The objective of this paper is to present the well revival strategy for gravel pack completion with liquid loading issue. Well NB-X is a high deviated gas well which was completed with 2 Sliding Sleeve Door-Gravel Pack (SSD-GP) zones and tubingless section. Since this well is a gas well with high water production, sudden unplanned shutdown can lead to a liquid loading issue. Revival well strategy by offloading the well to atmospheric was still not able to recover production as before the shutdown due to the high liquid column in the well. Therefore, a well intervention operation is needed to revive the well. The strategy was initiated by conducting a bottom hole monitoring survey to identify water sources. Production Logging Tool (PLT) was used to precisely monitor pressure, temperature, water holdup, and fluid rate along the wellbore for further water source and production allocation analysis. Once the water source zones have been identified, GP zone change for water shut-off (WSO) operation was requested. There are several means to execute zone change and unloading that are commonly used in Offshore Mahakam field each of which has selective economic consideration based on the expected well potential. A comparative study both for zone change (slickline, electricline tractor-stroker, and coiled tubing) and unload (N2 injection with coiled tubing) is performed to decide the most efficient way to revive the well. Operations started with a slickline zone change to close the water zone followed by production logging, however due to high inclination, it was found that the target zone was not fully closed. Based on the comparative study, zone change and unloading with coiled tubing (CT) was the most efficient strategy with cost saving for about 83% compared to the other means. Zone change and unloading can safely and efficiently be performed with CT followed by a production test via Multi-Phase Flow Meter (MPFM) while keeping the CT string inside the tubing to perform as a velocity string until gas production target is obtained. Well revival strategy on well NB-X was proven to be able to revive 100% well production of 18 MMscfd within a very short time period from the shutdown event. Comparative study between coiled tubing and electricline tractor-stroker for zone change and unloading was critical since the offshore area have many challenges such as unpredictable weather, limited availability of transportation units, efficiency of setting up units from and to the platform, and also the callout cost both for the equipment and personnel between the two which ends with the selection of coiled tubing as the most efficient way for this case.

Deliverability of a field shall be reflected through its hydrocarbon production. In offshore fields, the backbone for stability of production comes from drilling and well intervention operations. One makes new wells while the other maintains existing wells to minimize impact of the decline. Nevertheless, these operations may become a double-edge sword for production. For example, rig activities that shut in existing wells in an offshore platform create production loss of that field. This situation may be ludicrous, but it is a dire consequence for mature/sensitive wells, in which potential loss might be proportional to shut in duration required. This ironic situation prompts two (2) challenges which are to maintain production existing wells and to start production of new wells while respecting the safety aspect in operation. Thus, in order to overcome these challenges, an integrated optimization of SIMOPS between drilling, well intervention and production is ushered in X-1 drilling campaign where production activities continue and well intervention operates under cantilever of the jackup rig during the whole drilling campaign.PT Pertamina Hulu Mahakam (PHM) delivers one well in offshore area between 17-25 days in average, depending on the well type. As a continuous saving initiative process, every possible scenario was exercise to optimize cost and three (3) objectives were identified for cost optimization which are to reduce the shortfall of existing wells by re-perforation to revive well, optimize rig duration at respective wells safely through offline well intervention activities and accelerate the production of new wells. As a result, all three (3) objectives had been achieved during the complex campaign with deliverability including no LTI during operation, three (3) new wells , two (2) workover and sidetracked wells with longer open hole record at X-1, offline well intervention activities (perforation) of existing well at X-1, offline production activities to revive existing wells at X-1 through offload to atmosphere and offline well connection activities for new wells (earlier). In the final analysis, integrated SIMOPS optimization generates production gain and enhances cost effectiveness safely. This paper shall provide the methodology to design and prepare an integrated SIMOPS as well as the corresponding result and lesson learnt.